Mitral annular calcification (MAC) is common in patients with severe aortic stenosis (AS); however, the impact of its severity and associated mitral valve dysfunction (MVD) on patient outcomes remains unclear.

This study aims to assess the influence of MAC severity and MVD on outcomes in individuals with severe AS.

This retrospective study included 613 patients with severe AS. Patients were categorized by echocardiographic MAC severity and the presence of MVD, defined as a mean transmitral gradient (mTMG) ≥5 mmHg.

In total, 309 (50.4%) of the 613 patients had MAC (44% mild, 40% moderate and 16% severe), and 21% also displayed MVD. Patients with MAC had a lower six-year survival (47 ± 3% vs. 64 ± 3%, log-rank P < 0.001) even after adjustment for covariates of potential prognostic impact (adjusted HR [95% CI] = 1.43[1.08–1.90]) ( Fig. 1 ). Severe MAC was associated with being older, being female, higher comorbidity scores and high pulmonary pressures (all P < 0.05), and with a lower six-year survival (23 ± 7%) than mild (55 ± 5%) or moderate MAC (50 ± 5%) ( Fig. 1 ). Patients with both MAC and MVD had a six-year survival of 28 ± 7%, markedly lower than the 53 ± 4% for those with MAC but not MVD. Multivariable analysis indicated that severe MAC (adjusted HR [95% CI] = 2.75 [1.67–4.50]) and MVD (adjusted HR [95% CI] = 2.08 [1.36–3.15]) were independent predictors of death ( Fig. 1 ).

MAC is highly prevalent in patients with severe AS, affecting more than 50%. It is associated with shorter survival, particularly if MAC is severe or the patient also has MVD. These findings highlight the importance of evaluating MAC severity and mTMG in AS patients to guide clinical decisions.